SEASON 6, EPISODE 602 -
"Shawn, Gus, Lassiter, and Woody the coroner wake up in the Psych Office having no recollection of what happened the night before. When a body shows up dead, all leads initially point to our guys as being the culprits, but since they have no idea why they have no memory of this, they conclude that someone must have drugged them. From there, they conduct an investigation using clues and blurred Shawn Vision Flashbacks in order to exonerate themselves as well as find the real killer.